J. M. Glauser & Sons Ltd. was a British manufacturer. They were contractors to the War Office, Air Ministry, Government of India, amongst others.
The company was established in 1929 by Jean Maurice Glauser, a Naturalized British subject of Swiss origin.
In 1938/39, due to the expansion in business, the company bought the old St. James's Laundry in Bensham Manor Road, Thornton Heath, Surrey, and set up a new works (Bridge Buildings). A couple of years later, the company also took over the lease of shops at 349-351 Whitehorse Road, Croydon, where they set up their Head Office.
J.M. Glauser & Sons' scope of production also included equipment such as Braillewriters for the Royal National Institute for the Blind.
The company was wound up in 1956 when the founder retired.
Also made the Stenotype Braillewriter:-
The one in the image and variations, are the WW2 stereoscopes that are usually seen in films and documentaries, so it probably is rare.
The image is from the icehouse at Hughenden Manor.